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  5. UE12BT: Kaiju No. 8 Release Event Cards
  6. Childhood Promise

Union Arena · UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-075 · Common

Childhood Promise

Union Arena card price for Childhood Promise: $0.57 market, from $0.20 at the cheapest listing, Normal printing, updated Oct 20, 2026. Full price history since Nov 6, 2025 below.

Market price · Normal · Oct 20, 2026
$0.57
−3.4% this week · −3.4% in 30 days
Buy on eBay →
1 day0.0%
7 days−3.4%
30 days−3.4%
90 days+29.6%
1 year—
All time−40.0%

Sellers right now

$0.20lowest listing$2.28highest
Market price$0.57
Mid listing$0.62
30-day avg$0.59

Market price is what a near-mint copy actually sold for. The cheapest listing is what a seller asks today — on thin markets the two differ a lot.

Where to buy

TCGplayer$0.57

One year

$0.4152-week low$0.9552-week high
In the range30%
All-time low$0.41
All-time high$0.95
First priceNov 6, 2025
Normal · market price
$0.38$0.59$0.80$1.00
$0.57
Nov 2025Mar 2026Jun 2026Oct 2026
TCGplayer market price · via tcgcsvtcgrate.com

Price story

Childhood Promise was released in October 2025. Launch-week prices are left out here: before supply arrives they are mostly guesses. The cheapest listing right now is $0.20, and the 30-day average market price is $0.59.

Printings

PrintingMarketLowHigh7d
Normal$0.57$0.20$2.28−3.4%

The card in play

Card type
Event
Series Name
Kaiju No. 8
Required Energy
2
Action Point Cost
1
Activation Energy
Green
Card text

Choose one character on your field and switch it to active. If the chosen character is "Kafka Hibino", "Kaiju No. 8", or "Mina Ashiro", choose up to one of your AP cards and switch it to active.

Trigger

[Draw] Draw a card.

Other printings of Childhood Promise

1 more · $0.07 – $0.57
All printings
Childhood Promise (UE12BT/KJ8-1-075), Kaiju No. 8 — Union Arena card price +16.7% 7d Childhood Promise UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-075 $0.07

Also in UE12BT: Kaiju No. 8 Release Event Cards

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Full set
Now Leave the Rest to Me (UEPR/KJ8-1-074), Kaiju No. 8 Release Event Cards — Union Arena card price 0.0% 7d Now Leave the Rest to Me UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-074 $9.51 Soshiro Hoshina (029) (UEPR/KJ8-1-029), Kaiju No. 8 Release Event Cards — Union Arena card price 0.0% 7d Soshiro Hoshina (029) UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-029 $6.43 Kafka Hibino (Release Event Winner) (UEPR/KJ8-1-061), Kaiju No. 8 Release Event Cards — Union Arena card price +1.7% 7d Kafka Hibino (Release Event Winner) UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-061 $5.46 Kikoru Shinomiya (016) (UEPR/KJ8-1-016), Kaiju No. 8 Release Event Cards — Union Arena card price 0.0% 7d Kikoru Shinomiya (016) UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-016 $4.55 This Is Who I Am Right Now (UEPR/KJ8-1-036), Kaiju No. 8 Release Event Cards — Union Arena card price −7.4% 7d This Is Who I Am Right Now UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-036 $4.27